So, I'm going to apologize upfront, but I'm never coming back to this. Which makes it kind of suck that I'm giving you an alert to get this...but the story is near enough to finish that I can give the outline at least.
Sakura and Naruto would work to destablize the building and with it, disrupt the seal and allow ANBU to go help Hiruzen Sarutobi, this causes a lot more casualties and Hiruzen is still injured by the end of it. But the Sound 4 are reduced to Sakon, Ukon and Kidomaru.
Jiraiya fights and defeats Gaara pretty handidly
The remainder of Team 13 meanwhile hear the invasion going off and rush to the walls. There they fight off the Snake summons, but the strain is too much for them, and they both end up dying in the aftermath of Baki and the Sand Ninja blitzing them.
Team Eight is successfully saved by Kurenai leading the remaining Rookie Twelve.
In the aftermath discussion is had. Naruto has a break down at loosing everyone important to him except for the Hokage. Hiruzen talks to him and they hug it out. Jiraiya recruits Naruto to go find Tsunade to help heal Hiruzen. Kakashi takes Sakura under his wing, and begins training her as best he can.
The story would end with a somewhat aloof Itachi walking over the remains of Orochimaru, before Kisame says that the container has been seen over in Otakafu Gai.
Originally I planned to do a sequel of sorts set up after that...but that's not happening now. So yeah sorry for the let down here, but hope it gives some closure.